The British Army has not been at war for three years but, even so, it faces one of its biggest challenges to date.

The rise of the fundamentalist Islamic State, the threat of a new cold war on Europe’s eastern border and conflict in Africa is putting a new pressure on the armed forces at a time of budgetary cuts and growing opposition to military intervention.

In this three-part series, cameras go behind the scenes with our troops, kicking off in Iraq, where the Army is training Kurdish recruits to liberate Mosul from ISIS.

‘We’re not doing the fighting,’ stresses General Rupert Jones. ‘We’re here to support the Iraqi security forces. It’s important that they liberate their own country.’